An investigation by the Chartered Trading Standards Institute found that over 90% of children’s Halloween costumes purchased from online marketplaces failed UK safety requirements, with 91% non-compliance across 11 outfits tested.

Of 11 randomly purchased costumes from third‑party sellers on major platforms (OnBuy, Amazon, eBay, AliExpress, Shein, TikTok Shop), 10 were non‑compliant with UK safety requirements, signaling broader compliance issues beyond visible labeling.

The CTSI identified that 91% of children’s costumes sold by overseas third‑party sellers on online marketplaces did not meet UK product safety requirements.

London Fire Brigade safety tips recommend avoiding naked flames, using battery‑operated candles or glow sticks, layering costumes with regular clothes, teaching children fire safety, and adding reflective elements for visibility.

A lack of safety and traceability information makes it hard for parents to assess risk and for regulators to identify the importer or manufacturer responsible.

CTSI consumer guidance urges buying from reputable retailers (prefer UK‑based sellers on marketplaces), checking for UKCA/CE marks and manufacturer/importer details, reading safety information, researching sellers, verifying recalls on GOV.UK, and reporting suspicious listings to the marketplace and Trading Standards.

Costume legal requirements include displaying a UKCA or CE safety mark, listing the name and address of a UK manufacturer or importer, and clear warnings such as ‘keep away from fire’; non‑compliant designs can be classified as unsafe toys.

Flammability standards apply to children’s fancy dress costumes, which should show UKCA or CE markings and include the name and address of a UK‑based manufacturer or importer, with warnings to keep away from fire in some cases.

Common safety issues include missing safety warnings, lack of traceability information, and designs with potential strangulation or entanglement risks from long ribbons, cords, or flowing fabric.

One OnBuy listing featured a sexualised description for a costume intended for children aged 3–8 and had no labelling, underscoring marketplace listing concerns.

Non‑compliance encompassed missing safety warnings, lack of traceability, and broader labelling and compliance failures, raising questions about how marketplaces and sellers verify listings.

Parents are advised to buy from recognizable brands and reputable retailers, especially those aligned with the British Retail Consortium’s voluntary flammability Code of Practice, to reduce risk.